Hi Ross!
I hope it’s ok if i answer, also I’m quite new here to Creative Cow.
There’s an effect in After effects called “Typewriter”. Use the text tool to write your text, then go to the Effects browser and look for Animate in/ Typewriter. The rest should be really simple.
You could also draw a rectangle with the same background colour of the objects behind the text and put it on your text and change the path of it, so it reveals slowly your text. Or simply change the position of the rectangle and move it to the side. Make sure, the rectangel layer is on top of the text layer.